Dehydration

Dehydration happens when your body loses more fluid than it takes in. The signs of dehydration in kids can show up quickly with vomiting, diarrhea, or fever. Mild dehydration is easy to fix at home, but moderate dehydration needs care.

What Is It

Babies, young children, and older adults dehydrate fastest. Common causes are a stomach flu, food poisoning, fever, heat, and hard exercise. Chicago summers and winter stomach bugs both bring more cases.

Symptoms

In babies and young children:

Fewer wet diapers, or none in 6 hours
No tears when crying
Dry mouth and lips
Sunken eyes, or a sunken soft spot on a baby’s head
Unusual sleepiness or fussiness

In older children and adults:

Thirst and dark yellow urine
Headache
Dizziness when standing
Tiredness
Muscle cramps

Not sure how dehydrated? Mild dehydration means thirst and darker urine. Moderate dehydration adds dizziness, very little urine, and a dry mouth, and needs care today.

Treatment

At your visit: A provider checks vital signs and signs of dehydration and looks for the cause, like vomiting or fever. Medicine for nausea can help fluids stay down. IV fluids may be used when drinking is not enough.

At home:

Small, frequent sips of an oral rehydration drink
For babies, keep breastfeeding or formula in small, frequent feeds
Avoid soda and juice for young children, which can worsen diarrhea
Frozen pops made from an oral rehydration drink

Most mild dehydration improves within a few hours of steady sipping.

When to Get Care for Dehydration

Watch at Home

Thirst and slightly darker urine
Still urinating every few hours
Keeping small sips down

Come to Urgent Care Today

Vomiting that keeps fluids from staying down
A child with fewer wet diapers or bathroom trips
Dizziness when standing
A dry mouth and very dark urine
Diarrhea for more than a few days

Go to the Emergency Department

No urine for 8 hours or more
Confusion, extreme sleepiness, or hard to wake
Fainting, or a racing heart at rest
A baby with sunken eyes, a sunken soft spot, and no tears
A baby under 3 months who will not feed

FAQ

What are the signs of dehydration in kids?

The signs of dehydration in kids include fewer wet diapers or bathroom trips, no tears when crying, a dry mouth, and unusual sleepiness. A sunken soft spot on a baby’s head is a sign of more serious dehydration.

How do you rehydrate fast?

The fastest way to rehydrate at home is small, frequent sips of an oral rehydration drink, which replaces both water and salts. If you cannot keep fluids down, IV fluids at urgent care work faster.

How can I tell if my toddler is dehydrated?

A dehydrated toddler pees less often, has dark urine, cries without tears, and may be cranky or unusually sleepy. No wet diaper in 6 hours needs to be checked.

Can dehydration cause a headache?

Yes, dehydration commonly causes a headache, along with tiredness and dizziness. Drinking fluids usually eases a dehydration headache within an hour or two.

Are sports drinks good for dehydration?

Sports drinks are fine for mild dehydration from sweating in older kids and adults. For vomiting or diarrhea, especially in young children, an oral rehydration drink works better because it has less sugar and more salt.

Can urgent care treat dehydration?

Yes, urgent care can treat dehydration. At Vitality Urgent Care, a provider can check how dehydrated you are, and IV fluids are available when needed.

Last reviewed October 2026